US9328019B2 - Process to produce a durable concrete at hot ambient conditions - Google Patents

Process to produce a durable concrete at hot ambient conditions Download PDF

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US9328019B2
US9328019B2 US14/425,949 US201314425949A US9328019B2 US 9328019 B2 US9328019 B2 US 9328019B2 US 201314425949 A US201314425949 A US 201314425949A US 9328019 B2 US9328019 B2 US 9328019B2
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cementitious
cement
composition
concrete
cementitious composition
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US20150218048A1 (en
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Wolfram Franke
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Yara International ASA
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    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B14/00—Use of inorganic materials as fillers, e.g. pigments, for mortars, concrete or artificial stone; Treatment of inorganic materials specially adapted to enhance their filling properties in mortars, concrete or artificial stone
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B22/00—Use of inorganic materials as active ingredients for mortars, concrete or artificial stone, e.g. accelerators or shrinkage compensating agents
    • C04B22/08—Acids or salts thereof
    • C04B22/085—Acids or salts thereof containing nitrogen in the anion, e.g. nitrites
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
    • C04B28/02—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing hydraulic cements other than calcium sulfates
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
    • C04B28/02—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing hydraulic cements other than calcium sulfates
    • C04B28/04—Portland cements
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B40/00—Processes, in general, for influencing or modifying the properties of mortars, concrete or artificial stone compositions, e.g. their setting or hardening ability
    • C04B40/0028—Aspects relating to the mixing step of the mortar preparation
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B7/00—Hydraulic cements
    • C04B7/24—Cements from oil shales, residues or waste other than slag
    • C04B7/26—Cements from oil shales, residues or waste other than slag from raw materials containing flue dust, i.e. fly ash
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
    • C04B2111/10—Compositions or ingredients thereof characterised by the absence or the very low content of a specific material
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
    • C04B2111/76—Use at unusual temperatures, e.g. sub-zero
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
    • Y02W30/00—Technologies for solid waste management
    • Y02W30/50—Reuse, recycling or recovery technologies
    • Y02W30/91—Use of waste materials as fillers for mortars or concrete

Definitions

  • the invention relates to the use of calcium nitrate for producing a cementitious composition and/or a cementitious solid at high ambient temperatures.
  • the invention is directed to ensuring sufficient hydration by a limitation of the maximum hydration temperature.
  • this invention is especially of interest for pre-cast concrete using heat or on-site casted concrete in hot ambient conditions or in hot geographical regions.
  • Hydration is an exothermic reaction, which means that it generates heat, and that reactions proceed faster when the concrete is hot.
  • Quick reacting cements like CEM I 52.5 R, produce comparatively quickly high temperatures, but as many reactions happen within a short time, the heat production is high, too, and as a consequence of heat flow limitation due to thermal resistance of concrete and the high ambient temperature, the heat accumulates in the concrete—and the maximum temperature may exceed 60° C. This may lead to strong deformations and therefore induce cracking, as well as ettringite formation afterwards.
  • Retarders provide that the heat release is distributed over a longer time. Retarders can be added at the plant or on the job site to delay concrete setting time, which can be very quick when the concrete is hot. Retarders provide extra time but they also give the concrete more time to dry out, so curing is critical. Usually, the use of retarders also comes at the price of delayed setting.
  • Concrete is a composite construction material composed primarily of aggregate, cement, and water.
  • the aggregate is generally a coarse gravel or crushed rocks such as limestone, or granite, along with a fine aggregate such as sand.
  • the cement commonly Portland cement, and other cementitious materials such as fly ash and slag cement, serve as a binder for the aggregate.
  • Various chemical admixtures are also added to achieve varied properties.
  • Water is mixed with the dry concrete mixture, which enables it to be shaped (typically poured or casted) and then solidified and hardened (cured, set) into rock-hard strength concrete through a chemical process called hydration. The water reacts with the cement, which bonds the other components together, finally creating a robust stone-like material. Concrete can be damaged by many processes, such as the freezing of water trapped in the concrete pores.
  • Concrete is widely used for making architectural structures, foundations, brick/block walls, pavements, bridges/overpasses, motorways/roads, runways, parking structures, dams, pools/reservoirs, pipes, footings for gates, fences and poles and even boats.
  • a cementitious composition should be interpreted as comprising anyone of a mortar composition, a concrete composition, and a cement paste composition, which has not been casted, cured, hydrated, set and/or hardened.
  • a mortar composition comprises at least a fine aggregate, such as sand and cement.
  • a cement paste composition comprises at least cement.
  • a cementitious composition does not contain added water in such amounts that setting starts. In this respect, one could also speak of a cementitious composition in the dry state.
  • the cementitious composition is produced by adding all ingredients together and thoroughly mixing said ingredients until a homogeneous composition is obtained.
  • a cementitious solid should be interpreted as the casted, cured, hydrated, set and/or hardened cementitious composition, comprising anyone of a mortar, a concrete and a cement paste and water.
  • a cementitious solid is usually obtained by adding water to a cementitious composition, which initiates the curing process.
  • the cementitious solid is produced by adding water to the cementitious composition.
  • hot ambient conditions are defined as conditions with an ambient temperature of 21° C. or more, such as more than 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, or 44° C.
  • hot ambient conditions are defined as conditions with an ambient temperature in the range of 25 to 45° C., more preferably 30 to 45° C., most preferably 35 to 45° C.
  • the high amount of calcium nitrate in the compositions according to the invention shifts part of the reactions to even earlier stages than in the prior art.
  • the approach by Justnes et al. aims on early setting but slow hydration and low hydration heat release.
  • the retardation effect originates from preventing reactions (by using the strong setting retardant) whereas our invention is aimed at shifting accelerations to early stages to avoid reactions (and heat release) later on in the setting and hardening process.
  • the invention relates to the use of calcium nitrate for producing a cementitious composition and/or a cementitious solid at high ambient temperatures in the range of from 21 to 45° C., preferably in the range of from 30 to 45° C., more preferably in the range of from 35 to 45° C., wherein the cementitious composition and/or the cementitious solid comprises at least 3 weight % of calcium nitrate, relative to the weight of the cement.
  • the invented process has the ability to cool down a producing a cementitious composition and/or a cementitious solid that is being cured at hot ambient conditions, in particular at temperatures of 21° C. or above. Therefore, the process can limit the maximum occurring temperature only to the level of the ambient temperature.
  • Calcium nitrate is an inorganic compound with the formula Ca(NO 3 ) 2 .
  • This colourless salt absorbs moisture from the air and is commonly found as a tetrahydrate. It is mainly used as a component in fertilizers.
  • a variety of related salts are known including calcium ammonium nitrate decahydrate and calcium potassium nitrate decahydrate.
  • Different calcium nitrate salts are available from Yara International ASA (Oslo,
  • NitCal a solid with a concentration of about 78 weight % of calcium nitrate
  • NitCal/K a solid with a concentration of about 76 weight % of calcium nitrate
  • NitCal Sol an aqueous liquid with a concentration of 50 weight % calcium nitrate
  • It may be used as a dry material (granulated or prilled) or as a liquid (for example, as an aqueous liquid in a concentration of 50 weight % calcium nitrate). It may also be used (and it acts) as a corrosion inhibitor, since the nitrate ion leads to formation of iron hydroxide, whose protective layer reduces corrosion of the concrete reinforcement.
  • the invention relates to a use according to the invention, wherein the cementitious composition and/or the cementitious solid comprises 3 to 5 weight % of calcium nitrate, relative to the weight of the cement.
  • fly ash blended cements such as a Portland fly ash cement (OEM II type)
  • OEM II type Portland fly ash cement
  • the cementitious composition and/or a cementitious solid is free, or at least comprises less than 0.1 weight %, relative to the weight of the cement, of a compound selected from the group of urea, citric acid and tartaric acid.
  • a quick Portland cement of the CEM I 52.5 class can be utilised for pre-cast concrete production to quickly deliver strength.
  • the water to cement ratio is in the range of 0.45 to 0.55. This is required to prevent drying out of the cementitious solid during curing.
  • the calcium nitrate is added to the water for preparing the cementitious composition. It is important that calcium nitrate is incorporated into the cementitious composition right from the start. It should be added prior to any plasticiser to increase impact on setting time.
  • the invention also relates to a method of curing a cementitious composition at high ambient temperatures in the range of 21 to 45° C. into a cementitious solid, wherein the method comprises the steps of:
  • FIG. 1 Temperature profile over time for slow-reacting cement paste samples cured at 20° C. ambient temperature.
  • FIG. 2 Temperature profile over time for slow-reacting cement paste samples cured at 45° C. ambient temperature.
  • FIG. 3 Temperature profile over time for fast-reacting cement paste samples cured at 21° C. ambient temperature.
  • FIG. 4 Peak shift of maximum temperature as function of dosage of calcium nitrate and curing temperature for slow-reacting cement paste samples.
  • Cement paste samples with a CEM II/A 42.5 fly ash cement (slow reacting cement) were prepared. Sample size was 500 ml. The temperature was measured in the sample core. Samples were cured at 20° C. ambient temperature. Calcium nitrate was added in weight % amounts relative to the weight of the cement. The temperature profile is shown in FIG. 1 . As a reference, sample ( 1 ) was prepared without calcium nitrate. The addition of 1 weight % of calcium nitrate (sample 2 ) increased the temperature slightly and the setting was also shifted slightly towards an earlier moment in time. The addition of 4 weight % of calcium nitrate (sample 3 ) increased the maximum temperature significantly, but hydration reactions took place far earlier in time. In addition, the period without significant heat release (in samples ( 1 ) and ( 2 ) between 1 and 4 hours of the experiment) is overrun by the high dosage calcium nitrate treated sample ( 3 ) and setting starts very early.
  • Cement paste samples with a CEM II/A 42.5 fly ash cement (slow reacting cement) were prepared.
  • Sample size was 500 ml. Temperature was measured in the sample core. Samples were cured at 45° C. ambient temperature in a controlled water bath. Calcium nitrate was added in weight % amounts relative to the weight of the cement. The temperature profile is shown in FIG. 2 .
  • the presence of 4 weight % calcium nitrate in sample ( 2 ) reduced the temperature and the setting was shifted to an earlier stage in the process compared to an untreated sample ( 1 ).
  • sample ( 3 ) 0.5 weight % of a plasticizer (modified lignosulphonate, MLS) was added in addition to calcium nitrate, and the retarding effect can be clearly seen in FIG. 2 .
  • a plasticizer modified lignosulphonate, MLS
  • Calcium nitrate is also able to cool (fast-reacting) cement.
  • Cement paste samples with a CEM I 52.5 cement (fast reacting) are prepared. Sample size is 500 ml. Temperature is measured in the sample core. Samples are cured at 21° C. ambient temperature. Sample ( 1 ) as reference is close to critical temperature level. Calcium nitrate is added with relation to cement weight in %. Addition of 1% calcium nitrate in sample ( 2 ) reduces the peak temperature slightly. Increased dosages to 4% (sample ( 3 )) and 5% (sample ( 4 )) shifts initial setting to almost immediate, and hydration temperature is reduced significantly by more than 10 degree Celsius.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Ceramic Engineering (AREA)
  • Materials Engineering (AREA)
  • Structural Engineering (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Civil Engineering (AREA)
  • Curing Cements, Concrete, And Artificial Stone (AREA)
US14/425,949 2012-09-25 2013-09-23 Process to produce a durable concrete at hot ambient conditions Active US9328019B2 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
NO20121087A NO339038B1 (no) 2012-09-25 2012-09-25 Anvendelse av kalsiumnitrat for å fremstille en sementbasert sammensetning og/eller et sementbasert fast legeme og fremgangsmåte for å herde en sementbasert sammensetning ved høye omgivelsestemperaturer.
NO20121087 2012-09-25
PCT/EP2013/069700 WO2014048870A1 (en) 2012-09-25 2013-09-23 Process to produce a durable concrete at hot ambient conditions

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US20150218048A1 US20150218048A1 (en) 2015-08-06
US9328019B2 true US9328019B2 (en) 2016-05-03

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US (1) US9328019B2 (de)
EP (1) EP2900619B1 (de)
BR (1) BR112015006448B1 (de)
CA (1) CA2884350C (de)
ES (1) ES2835226T3 (de)
MX (1) MX347866B (de)
NO (1) NO339038B1 (de)
PL (1) PL2900619T3 (de)
PT (1) PT2900619T (de)
WO (1) WO2014048870A1 (de)

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Publication number Priority date Publication date Assignee Title
NO20131471A1 (no) 2013-11-05 2015-05-06 Yara Int Asa Størkningsakselerator for tørr mørtelblanding, prosess for produksjon av en slik størkningsakselerator, en tørr mørtelblanding og en mørtelpasta
BR112018009232B1 (pt) * 2015-11-10 2023-01-10 Yara International Asa Composição de concreto vertível e curável compreendendo nitrato de cálcio, uso de nitrato de cálcio em concreto reforçado com aço para obter uma elevada resistência à carbonatação, sólido de concreto reforçado com aço e método para produzir o mesmo

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4747877A (en) 1985-12-12 1988-05-31 Skw Trostberg Ag Chloride-free hardening accelerant for portland cement and process thereof
US5176753A (en) 1986-09-19 1993-01-05 Brook John W Concrete admixture compositions
GB2354235A (en) 1998-03-06 2001-03-21 Ask Corp Cement moldings containing vegetable fiber and method for producing the same
US6273191B1 (en) 1999-07-15 2001-08-14 Halliburton Energy Services, Inc. Cementing casing strings in deep water offshore wells
US20050223717A1 (en) 2004-01-06 2005-10-13 Dryair Inc. Method and apparatus for cooling concrete during curing
EP1731491A1 (de) 2005-06-10 2006-12-13 Lafarge Kaliumsalz enthaltende Schnellbinderzusammensetzungen für Betonteile und -werke
WO2009016230A2 (en) * 2007-08-02 2009-02-05 Construction Research & Technology Gmbh Cement-based grout composition
EP2090560A1 (de) 2008-01-30 2009-08-19 Schlumberger Holdings Limited Chemische Aktivierung des Abbindens von Zement
WO2012175660A1 (en) * 2011-06-24 2012-12-27 Lafarge Hydraulic composition submitted to a thermal treatment

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4747877A (en) 1985-12-12 1988-05-31 Skw Trostberg Ag Chloride-free hardening accelerant for portland cement and process thereof
US5176753A (en) 1986-09-19 1993-01-05 Brook John W Concrete admixture compositions
GB2354235A (en) 1998-03-06 2001-03-21 Ask Corp Cement moldings containing vegetable fiber and method for producing the same
US6273191B1 (en) 1999-07-15 2001-08-14 Halliburton Energy Services, Inc. Cementing casing strings in deep water offshore wells
US20050223717A1 (en) 2004-01-06 2005-10-13 Dryair Inc. Method and apparatus for cooling concrete during curing
EP1731491A1 (de) 2005-06-10 2006-12-13 Lafarge Kaliumsalz enthaltende Schnellbinderzusammensetzungen für Betonteile und -werke
US20080308013A1 (en) 2005-06-10 2008-12-18 Chryso Rapid Binder Compositions Containing a Calcium Salt for Concrete Components and Structures
WO2009016230A2 (en) * 2007-08-02 2009-02-05 Construction Research & Technology Gmbh Cement-based grout composition
EP2090560A1 (de) 2008-01-30 2009-08-19 Schlumberger Holdings Limited Chemische Aktivierung des Abbindens von Zement
WO2012175660A1 (en) * 2011-06-24 2012-12-27 Lafarge Hydraulic composition submitted to a thermal treatment

Non-Patent Citations (4)

* Cited by examiner, † Cited by third party
Title
Clemmens et al., "Influence of Setting Accelerators on Chemical Shrinkage of Portland Cement", American Concrete Institute, SP-200, 2001, pp. 235-249.
International Preliminary Report on Patentability issued Dec. 15, 2014 in International (PCT) Application No. PCT/EP2013/069700.
International Search Report and Written Opinion of the International Search Authority issued Nov. 22, 2013 in International (PCT) Application No. PCT/EP2013/069700.
Justnes et al., "Hardening retarders for massive concrete", American Concrete Institute, SP-253, 2008, pp. 41-56.

Also Published As

Publication number Publication date
CA2884350A1 (en) 2014-04-03
ES2835226T3 (es) 2021-06-22
US20150218048A1 (en) 2015-08-06
BR112015006448B1 (pt) 2021-04-27
WO2014048870A1 (en) 2014-04-03
PT2900619T (pt) 2021-01-28
EP2900619B1 (de) 2020-11-11
BR112015006448A2 (pt) 2017-07-04
MX2015003547A (es) 2015-10-26
EP2900619A1 (de) 2015-08-05
NO339038B1 (no) 2016-11-07
NO20121087A1 (no) 2014-03-26
MX347866B (es) 2017-05-17
PL2900619T3 (pl) 2021-05-04
CA2884350C (en) 2017-05-09

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